x1,y1,x2,y2,x3,y3 = 0,0,0,100,200,0

xp,yp = eval(input("请输入一个点："))

x1_2 = (x2-x1)*(yp-y1) - (y2-y1)*(xp-x1)
x2_3 = (x3-x2)*(yp-y2) - (y3-y2)*(xp-x2)
x3_1 = (x1-x3)*(yp-y3) - (y1-y3)*(xp-x3)

if x1_2<0 and x2_3<0 and x3_1<0:
    print("该点在三角形内部")
elif x1_2==0 or x2_3==0 or x3_1==0:
    print("该点在三角形边上")
else:
    print("该点在三角形外部")
